Linux-Crypto Archive on lore.kernel.org
 help / color / Atom feed
From: Marcelo Henrique Cerri <marcelo.cerri@canonical.com>
To: "Stephan Müller" <smueller@chronox.de>
Cc: herbert@gondor.apana.org.au, linux-crypto@vger.kernel.org,
	Tianjia Zhang <tianjia.zhang@linux.alibaba.com>,
	ard.biesheuvel@linaro.org, nhorman@redhat.com, simo@redhat.com
Subject: Re: [PATCH v3 0/5] DH: SP800-56A rev 3 compliant validation checks
Date: Tue, 21 Jul 2020 08:35:24 -0300
Message-ID: <20200721113524.kdfs4nwn2oacexqx@valinor> (raw)
In-Reply-To: <2544426.mvXUDI8C0e@positron.chronox.de>


[-- Attachment #1: Type: text/plain, Size: 3075 bytes --]

Reviewed-by: Marcelo Henrique Cerri <marcelo.cerri@canonical.com>
Tested-by: Marcelo Henrique Cerri <marcelo.cerri@canonical.com>

On Mon, Jul 20, 2020 at 07:05:45PM +0200, Stephan Müller wrote:
> Hi,
> 
> This patch set adds the required checks to make all aspects of
> (EC)DH compliant with SP800-56A rev 3 assuming that all keys
> are ephemeral. The use of static keys adds yet additional
> validations which are hard to achieve in the kernel.
> 
> SP800-56A rev 3 mandates various checks:
> 
> - validation of remote public key defined in section 5.6.2.2.2
>   is already implemented in:
> 
>   * ECC: crypto_ecdh_shared_secret with the call of
>     ecc_is_pubkey_valid_partial
> 
>   * FFC: dh_compute_val when the req->src is read and validated with
>     dh_is_pubkey_valid
> 
> - validation of generated shared secret: The patch set adds the
>   shared secret validation as defined by SP800-56A rev 3. For
>   ECDH this only implies that the validation of the shared secret
>   is moved before the shared secret is returned to the caller.
> 
>   For DH, the validation is required to be performed against the prime
>   of the domain parameter set.
> 
>   This patch adds the MPI library file mpi_sub_ui that is required
>   to calculate P - 1 for the DH check. It would be possible, though
>   to simply set the LSB of the prime to 0 to obtain P - 1 (since
>   P is odd per definition) which implies that mpi_sub_ui would not
>   be needed. However, this would require a copy operation from
>   the existing prime MPI value into a temporary MPI where the
>   modification can be performed. Such copy operation is not available.
>   Therefore, the solution with the addition of mpi_sub_ui was chosen.
> 
>   NOTE: The function mpi_sub_ui is also added with the patch set
>   "[PATCH v5 2/8] lib/mpi: Extend the MPI library" currently sent
>   to the linux-crypto mailing list.
> 
> - validation of the generated local public key: Patches 4 and 5 of
>   this patch set adds the required checks.
> 
> Changes to v2:
> 
> - add reference to GnuMP providing the basis for patch 2 and updating
>   the copyright note in patch 2
> 
> Changes to v1:
> 
> - fix reference to Gnu MP as outlined by Ard Biesheuvel
> - addition of patches 4 and 5
> 
> Marcelo Henrique Cerri (1):
>   lib/mpi: Add mpi_sub_ui()
> 
> Stephan Mueller (4):
>   crypto: ECDH - check validity of Z before export
>   crypto: DH - check validity of Z before export
>   crypto: DH SP800-56A rev 3 local public key validation
>   crypto: ECDH SP800-56A rev 3 local public key validation
> 
>  crypto/dh.c          | 38 +++++++++++++++++++++
>  crypto/ecc.c         | 42 +++++++++++++++++++++---
>  crypto/ecc.h         | 14 ++++++++
>  include/linux/mpi.h  |  3 ++
>  lib/mpi/Makefile     |  1 +
>  lib/mpi/mpi-sub-ui.c | 78 ++++++++++++++++++++++++++++++++++++++++++++
>  6 files changed, 172 insertions(+), 4 deletions(-)
>  create mode 100644 lib/mpi/mpi-sub-ui.c
> 
> -- 
> 2.26.2
> 
> 
> 
> 

-- 
Regards,
Marcelo


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 659 bytes --]

  parent reply index

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-10 10:09 [PATCH 0/3] DH: SP800-56A rev 3 compliant shared secret Stephan Müller
2020-07-10 10:10 ` [PATCH 1/3] crypto: ECDH - check validity of Z before export Stephan Müller
2020-07-10 10:10 ` [PATCH 2/3] lib/mpi: Add mpi_sub_ui() Stephan Müller
2020-07-10 14:42   ` Ard Biesheuvel
2020-07-10 15:10     ` Stephan Mueller
2020-07-10 10:15 ` [PATCH 3/3] crypto: DH - check validity of Z before export Stephan Müller
2020-07-12 16:38 ` [PATCH v2 0/5] DH: SP800-56A rev 3 compliant validation checks Stephan Müller
2020-07-12 16:39   ` [PATCH v2 1/5] crypto: ECDH - check validity of Z before export Stephan Müller
2020-07-12 18:02     ` Vitaly Chikunov
2020-07-15 13:17     ` Marcelo Henrique Cerri
2020-07-12 16:39   ` [PATCH v2 2/5] lib/mpi: Add mpi_sub_ui() Stephan Müller
2020-07-16  7:30     ` Herbert Xu
2020-07-16  8:41       ` Ard Biesheuvel
2020-07-16 12:50         ` Marcelo Henrique Cerri
2020-07-16 13:09           ` Ard Biesheuvel
2020-07-16 13:41             ` Marcelo Henrique Cerri
2020-07-16 13:53               ` Ard Biesheuvel
2020-07-16 14:23                 ` Marcelo Henrique Cerri
2020-07-16 14:37                   ` Ard Biesheuvel
2020-07-16 14:56                     ` Marcelo Henrique Cerri
2020-07-16 15:20                       ` Ard Biesheuvel
2020-07-12 16:40   ` [PATCH v2 3/5] crypto: DH - check validity of Z before export Stephan Müller
2020-07-15 13:17     ` Marcelo Henrique Cerri
2020-07-12 16:40   ` [PATCH v2 4/5] crypto: DH SP800-56A rev 3 local public key validation Stephan Müller
2020-07-15 13:18     ` Marcelo Henrique Cerri
2020-07-12 16:42   ` [PATCH v2 5/5] crypto: ECDH " Stephan Müller
2020-07-12 18:06     ` Vitaly Chikunov
2020-07-13  5:04       ` Stephan Mueller
2020-07-13  5:59         ` Vitaly Chikunov
2020-07-13  6:02           ` Stephan Müller
2020-07-15 13:19     ` Marcelo Henrique Cerri
2020-07-20 17:05   ` [PATCH v3 0/5] DH: SP800-56A rev 3 compliant validation checks Stephan Müller
2020-07-20 17:07     ` [PATCH v3 1/5] crypto: ECDH - check validity of Z before export Stephan Müller
2020-07-22 13:11       ` Vitaly Chikunov
2020-07-24 17:47       ` Neil Horman
2020-07-20 17:08     ` [PATCH v3 2/5] lib/mpi: Add mpi_sub_ui() Stephan Müller
2020-07-20 17:08     ` [PATCH v3 3/5] crypto: DH - check validity of Z before export Stephan Müller
2020-07-24 18:02       ` Neil Horman
2020-07-20 17:08     ` [PATCH v3 4/5] crypto: DH SP800-56A rev 3 local public key validation Stephan Müller
2020-07-20 17:09     ` [PATCH v3 5/5] crypto: ECDH " Stephan Müller
2020-07-21 11:35     ` Marcelo Henrique Cerri [this message]
2020-07-31 13:29     ` [PATCH v3 0/5] DH: SP800-56A rev 3 compliant validation checks Herbert Xu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200721113524.kdfs4nwn2oacexqx@valinor \
    --to=marcelo.cerri@canonical.com \
    --cc=ard.biesheuvel@linaro.org \
    --cc=herbert@gondor.apana.org.au \
    --cc=linux-crypto@vger.kernel.org \
    --cc=nhorman@redhat.com \
    --cc=simo@redhat.com \
    --cc=smueller@chronox.de \
    --cc=tianjia.zhang@linux.alibaba.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Crypto Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-crypto/0 linux-crypto/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-crypto linux-crypto/ https://lore.kernel.org/linux-crypto \
		linux-crypto@vger.kernel.org
	public-inbox-index linux-crypto

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-crypto


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git